Recording low-pressure gage.



0. J. MANNING.

RECORDING LOW PRESSURE GAGE.

APPLIOATION FILED 82M. 15, 1911.

1 ,O44,678. Patented Nov. 19, 1912.

UNITED STATES PATENT OFFICE.

CO LEMAN J. MANNING, OF MEDFORD, MASSACHUSETTS, ASSIGNOR TO AMERICANSTEAM GAUGE &; VALVE MANUFACTURING COMPANY, OF BOSTON, MASSACHU- SETTS,A CORPORATION OF NEW JERSEY.

RECORDING LOW-PRESSURE GAGE.

Specification of Letters Patent.

To all whom it concern:

Be it known that-,1, COLEMAN J. MANNING, a citizen ofthe United States,and a resident of Medford, in the county of Middlesex and State ofMassachusetts, have invented certain -new and useful Improvements inRecording Low-Pressure Gages, of which the following is a specification.

This invention relates .to devices for indicating or recordingvariations of pressure,

and has particular reference to that class of such devices in which theair or gas the pressure of which is to be indicated or re-- corded, isadmitted .to a plurality of connected disk-shaped expansible chambers,one of which operates a device for making a record on a revolving dial;

The object of the present invention s to provide a simple and sensitiveinstrument of the character mentioned, in which the necessary. amountofmovement will be imparted to the marker by a minimum number of theconnected chambers, the instrument being especiallyadapbed, owing to itsdelicacy or sensitiveness, to record the variations of pressurein deepmines so as .to give information of the presence ofgas mixed with theair, since such mixture increases the pressure. -When usedfor thisurpose, the instrument itself ma be setup a ove ground and have a smalltub improvementswhich I' will now proceed to describe and claim.

being broken out, o a gage embodyingmy invention; F ig. 2 is a detailsectional view, on a larger .scale, and showing a different number ofthe connected chambers; Fig; 3

is a View similar'to Fig. 2, but showing the result of increasedinternal pressure; Fig. 4

is" a detail view illustrating another. arrange. ment of the connectionsbetween the expansible chambers.

is shown as'containing a dial b-of a wellknown type, which dial, as isusual, is my tated by clock mechanism. An oscillatory e connected to thenip-- ple or inlet of the gage, which tube has its lower open end downin the mine.

, To theseendsithe invention consists in the lever c carries a marker d,such as a pen, for

making a record on the dial of fluctuation of pressure, said arm beingpivoted to the frame or casing at e. The inlet nipple for the connectionof the pipe (not shown) leading to the mine or elsewhere, is shown at f.

The expansible chambers g, of which there may be two, as shown in Figs.2 and 3, or

more, as shown in the other figures, are each;

constructed of two thin sheets of metal, prefr erably of disk form butnot necessarily so, said two sheets being connected at their ar gins toform a chamber adapted to be expanded or bulged at its sides by internalpressure. The lower chamber is connected to the inlet f and the upperchamber is preferably connected with the marker by the following means:Rigidly secured to the top of the upper chamber, as by lugs and a clampscrew 2', is an arm a" which extends beyond the margin of the chamberand'is connected by a link i with an arm 0 of the .marker lever c. I donot limit myself to this particular form of connections for operatingthe marker by movements of the upper chamber.

Each chamber 9 is connected with the next one by a short tube j, locatednear one margin or edge of the chambers. This causes the connectionbetween the chambers to be eccentric so that, under the influence ofinternal pressure, the chambers will diverge, as shown by comparingFigs. 2 and .3. And since the arm iextends beyond the chambers areshown, as in Figs. 2 and 3;

thus reducing the number of chambers to the minimum. 1

' It is to be noted especially that the marginal connections between thechambers are not direct that is, the walls of the chambers do not touchor connect directly, but only through the medium of the tubes Therefore,when internal pressure causes the sides of the chambers to bulge, theupper.

Patented Nov. 19, 1912..

side of the lower chamber causes the tube 9' to tilt or swing outward(see Fig. 3) and the bulging of the under side of the next higherchamber causes the median plane of that chamber to assume 'a reaterdegree of inclination than could resu t if the adjacent 'walls of thechambers were connected .di-

rectly together. The tube connections enable me to obtain with twochambers substantially as great a range of movement of the portion ofthe upper chamber which carries the lug i, as can be obtained from fourchambers having their sides directly united, Without tubes. \Vhether twochambers g are employed, or more, the tipping of the chamber or chamberssucceeding the lower one, results in a considerable amplitude ofmovement being imparted to the marker by a very small increase ofpressure.

If more than two chambers are used, a

. structure such as shown in Fig. 4 may be employed, the tubeconnections alternating instead of one being above another. Then themovements of thelug i will be in a substantial-lystraight line insteadof the curved path shown by comparing Figs. 2 and 3.

1. A pressure gage having a pressure actuated member consisting ofchambers arranged side by side, the opposing sides of eachchamber beingexpansible relatively to each other, the sides of adjacent chambershaving smallopenings close to their margins connected by a tube.

2. A pressure gage having an inlet, a

chamber communicating with said inlet and having a flexible side, asecond chamber having a flexible side spaced from the flexi- Ocpies ofthis patent may be obtained for ble side of the first mentioned chamber,whereby expansion will cause said flexible sides to move apart, and asmall pipe having its ends connected to marginal portions of saidflexible sides.

-3. A pressure gage having a pressure actuated member consisting of aplurality of chambers arranged side by side, the adjacent sides of eachchamber being flexible and spaced from each other whereby expansion willcausethe said flexible sides to move apart, said flexible sides havingsmall openings close to their margins, and a short pipe having one endconnected to the opening of one of the said sides and its other endconnected to the opening of the adjacent flexible side.

4. A pressure gage having a pressure actuated member consisting ofexpansible chambers arranged side by side," a small five cents each, byaddressing the Loxhmissioner of Patents, Washington, D. G.

